The present invention relates to a process and apparatus for the continuous production of a regular thin film of human and pet foodstuffs. In particular the invention extends to the use of such films in the production of layered products. The invention is particularly concerned with the production and use of regular films of confectionery such as nougat, caramel, chocolate, and sugar, as well as other human foodstuffs such as meat products, ice cream, baked product compositions and decorative butter and spreads.
Layered products, especially layered confectionery products, are well known. Generally they are formed by chocolate paste being applied to a so-called refiner roll from which a film is scraped and collected in an appropriate former to form the desired product. By controlling the speed of the refiner roll on which the chocolate paste is spread into a film, it is possible to remove the film as a continuous sheet. By varying the angle of the scraper blade, the film can be collected as a wrinkled, partially compressed bar of confectionery product of a length equal to the width of the roll. The width of the bar, or the quantity scraped from the roll can be mechanically controlled by intermittent stopping and starting of the forming roll. A take-off device then removes the formed bar from the scraper blade while the roll is stationary. The length of the separate bars may be further controlled by mechanical means such as small sharp protrusions at defined intervals along the scraper blade breaking the film into discrete lengths.
In some prior art examples the chocolate paste used in such processes has a higher fat content than is typical for regular chocolate products. Solid fragments of this chocolate may be fed into a breaker unit where they are kneaded before they are passed on to the refiner roll where they are formed into a film. In some cases, in addition to the kneading, some water, syrup, or other vehicle for adding water may be added to the paste to help generate a consistency which will enable it to be formed into a film. However care must be taken that this water is distributed evenly throughout the paste otherwise an irregular film and consequently irregular products will be formed.
In other prior art examples, solid fragments of tempered chocolate are fed into a breaker unit where they are broken before being passed on to a refiner roll where they are formed into a film. The fat content of the tempered chocolate will be lower than for the previous example, and there is also no need for the addition of any water to transform the chocolate into a state which can form a film.
The paste may be cooled on the refiner roll to further induce fat crystallisation in a controlled way and to thereby produce a stable film which can be removed as one piece by the scraper blade. The chocolate is also subjected to further cooling after it has been formed into the desired wrinkled, partially compressed shape to set the plasticised chocolate into a solid product.
FIG. 1 shows, in general form, one such process for the production of a layered chocolate product. Solid fragments of chocolate are kneaded into a paste 2 and fed to a series of rolls 4, 6, and 8 on which a film 10 of plasticised chocolate is formed. After a sufficient time period has elapsed to form the relatively uniform film at a suitable temperature to be moulded, arranged or otherwise formed into a layered product, the film is removed from the surface of roll 8 by means of a scraper 12. The layered product 14 is formed on the scraper and is transferred by any suitable means 16 to a conveyor 18 which passes the products 14 to a cooler 20.
There are some problems with the processes of the prior art for producing layered chocolate products. The process for forming the film of chocolate on the roller is unreliable which results in variations in film thickness and an inconsistent weight profile of the product. The consequence of this inconsistency is that each layered chocolate product produced has to be inspected in order that products which fail to meet the required standard are rejected. In some cases, an extra enrobing layer of foodstuff (normally more chocolate) is coated on the layered chocolate product both for additional strength and for aesthetic reasons. If the layered chocolate product has defects in the outer surface, extra enrobing foodstuff (e.g. chocolate) may be required to produce a smooth enrobing outer surface. This is not only inefficient but may also reduce the benefits of having a layered chocolate or other foodstuff product. Further, the use of a castellated doctor blade to cut the film into suitable lengths results in a large amount of the chocolate film passing round the roller and being reworked, thereby changing its properties, or causing inefficiencies.
An object of the present invention is to overcome the problems of the prior art systems as outlined above in connection with the production of layered chocolate products, and to apply the solution to the human and pet food industry in general. In particular, it is the object of the present invention to provide a method and apparatus for the production of a regular film of human or pet foodstuffs (for example chocolate, nougat, caramel, toffee, sugar, creams, ice creams, wafer batter, meat products, pet food etc. or combinations of these) which may subsequently be used in the production of a layered foodstuff product.